vendredi 17 juin 2016

Image above: The team in the control room on the 16 June 2016 as the first beam of particles are sent through the proton beam line to the AWAKE experiment (Image: Ans Pardons/CERN).

For the first time a beam of particles has been sent through the pioneering AWAKE experiment signaling the next stage of its commissioning.

This is a test beam, meaning its purpose is to see whether all the parts of the beam line to the experiment are working correctly, and that the magnets are aligning the beam in the correct way.

AWAKE (the Advanced Proton Driven Plasma Wakefield Acceleration Experiment) will be the first accelerator of its kind in the world. It is currently under construction, but hopes to test the concept that plasma wakefields driven by a proton beam could accelerate charged particles.

The proton beam has to travel along around 800 m of proton beam line through the 10 m plasma cell, which at the moment is just an empty tube as the plasma is not filled yet, then downstream are several detectors.

“What was really nice is that when we first sent the beam down the proton line to the experiment area, it immediately hit the last detector, verifying our calculations and installation. We can now move onto the next stage of commissioning. There is a strong and wonderful team behind this success,” explains Edda Gschwendtner, the project leader.

The beam comes from CERN’s Super Proton Synchrotron (SPS), which just celebrated its fortieth birthday.

“Now we have to do the real work, checking all the details, but it’s great that the very first test showed everything is very consistent. Yes, now we have the beam but we still have to measure and calibrate everything, like the beam instrumentation along the beam line,” says Edda.

AWAKE hopes to start collecting physics data by the end of the year. Next the team will finalise installation of the experiment, the laser and the full plasma cell.

If it works this technology will mean linear colliders in the future could be much shorter, and even table-top accelerators could be possible.

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 21 Member States.

The Super Proton Synchrotron (SPS), CERN’s second-largest accelerator, is celebrating its 40th birthday. But the 7-kilometre-circumference accelerator is not getting a break for the occasion: it will continue to supply the Large Hadron Collider (LHC) and several fixed-target experiments with protons and heavy ions.

The SPS began life in a particularly spectacular fashion. On 17 June 1976, the machine, a giant among its contemporaries, accelerated protons to 300 gigaelectronvolts (GeV) for the first time. During his announcement of the successful start-up to the CERN Council, the Director-General, John Adams, who had led the design of the SPS, requested authorisation to increase the brand-new accelerator’s energy. Just a few minutes later, it reached an energy of 400 GeV.

A second key moment for the accelerator came five years later, when, in a real technological masterstroke, it was transformed into a proton-antiproton collider. This revolutionary collider allowed the discovery of the W and Z bosons two years later, an achievement for which the Nobel prize was awarded in 1984.

Now an essential link in CERN’s accelerator complex, the energy of the SPS has been increased to 450 GeV and for 40 years the machine has been supplying various types of particles to dozens of different experiments, from the heavy-ion programme to studies of charge-parity violation (the imbalance between matter and antimatter) and of the structure of nucleons. At present, for example, it supplies particles to the COMPASS, NA61/Shine, NA62 and NA63 experiments, and it will shortly start sending protons to the new AWAKE project, which will test innovative acceleration techniques. The SPS also sends particles to test areas for equipment and detectors, including the HiRadMat project.

Since 1989, when its big brother, the Large Electron-Positron Collider (LEP), was commissioned, the SPS has served as an injector, forming the last-but-one link in the accelerator chain. It supplied LEP with electrons and positrons until the end of 2000. It now accelerates protons and lead ions for the LHC, which replaced the LEP in the 27-kilometre tunnel.

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 21 Member States.

This colorful and star-studded view of the Milky Way galaxy was captured when the NASA/ESA Hubble Space Telescope pointed its cameras towards the constellation of Sagittarius (The Archer). Blue stars can be seen scattered across the frame, set against a distant backdrop of red-hued cosmic companions. This blue litter most likely formed at the same time from the same collapsing molecular cloud.

The color of a star can reveal many of its secrets. Shades of red indicate a star much cooler than the sun, so either at the end of its life, or much less massive. These lower-mass stars are called red dwarfs and are thought to be the most common type of star in the Milky Way. Similarly, brilliant blue hues indicate hot, young, or massive stars, many times the mass of the sun.

A star’s mass decides its fate; more massive stars burn brightly over a short lifespan, and die young after only tens of millions of years. Stars like the sun typically have more sedentary lifestyles and live longer, burning for approximately ten billion years. Smaller stars, on the other hand, live life in the slow lane and are predicted to exist for trillions of years, well beyond the current age of the universe.

Hubble and the sunrise over Earth

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

Artist’s impression of a hot Jupiter exoplanet in the star cluster Messier 67

An international team of astronomers have found that there are far more planets of the hot Jupiter type than expected in a cluster of stars called Messier 67. This surprising result was obtained using a number of telescopes and instruments, among them the HARPS spectrograph at ESO’s La Silla Observatory in Chile. The denser environment in a cluster will cause more frequent interactions between planets and nearby stars, which may explain the excess of hot Jupiters.

A Chilean, Brazilian and European team led by Roberto Saglia at the Max-Planck-Institut für extraterrestrische Physik, in Garching, Germany, and Luca Pasquini at ESO, has spent several years collecting high-precision measurements of 88 stars in Messier 67 [1]. This open star cluster is about the same age as the Sun and it is thought that the Solar System arose in a similarly dense environment [2].

The star cluster Messier 67 in the constellation of Cancer

The team used HARPS, along with other instruments [3], to look for the signatures of giant planets on short-period orbits, hoping to see the tell-tale “wobble” of a star caused by the presence of a massive object in a close orbit, a kind of planet known as a hot Jupiters. This hot Jupiter signature has now been found for a total of three stars in the cluster alongside earlier evidence for several other planets.

A hot Jupiter is a giant exoplanet with a mass of more than about a third of Jupiter’s mass. They are “hot” because they are orbiting close to their parent stars, as indicated by an orbital period (their “year”) that is less than ten days in duration. That is very different from the Jupiter we are familiar with in our own Solar System, which has a year lasting around 12 Earth- years and is much colder than the Earth [4].

“We want to use an open star cluster as laboratory to explore the properties of exoplanets and theories of planet formation”, explains Roberto Saglia. “Here we have not only many stars possibly hosting planets, but also a dense environment, in which they must have formed.”

Wide-field view of the open star cluster Messier 67

The study found that hot Jupiters are more common around stars in Messier 67 than is the case for stars outside of clusters. “This is really a striking result,” marvels Anna Brucalassi, who carried out the analysis. “The new results mean that there are hot Jupiters around some 5% of the Messier 67 stars studied — far more than in comparable studies of stars not in clusters, where the rate is more like 1%.”

Astronomers think it highly unlikely that these exotic giants actually formed where we now find them, as conditions so close to the parent star would not initially have been suitable for the formation of Jupiter-like planets. Rather, it is thought that they formed further out, as Jupiter probably did, and then moved closer to the parent star. What were once distant, cold, giant planets are now a good deal hotter. The question then is: what caused them to migrate inwards towards the star?

There are a number of possible answers to that question, but the authors conclude that this is most likely the result of close encounters with neighbouring stars, or even with the planets in neighbouring solar systems, and that the immediate environment around a solar system can have a significant impact on how it evolves.

In a cluster like Messier 67, where stars are much closer together than the average, such encounters would be much more common, which would explain the larger numbers of hot Jupiters found there.

Co-author and co-lead Luca Pasquini from ESO looks back on the remarkable recent history of studying planets in clusters: “No hot Jupiters at all had been detected in open clusters until a few years ago. In three years the paradigm has shifted from a total absence of such planets — to an excess!”

Notes:

[1] Some of the original sample of 88 were found to be binary stars, or unsuitable for other reasons for this study. This new paper concentrates on a sub-group of 66 stars.

[2] Although the cluster Messier 67 is still holding together, the cluster that may have surrounded the Sun in its early years would have dissipated long ago, leaving the Sun on its own.

[3] Spectra from the High Resolution Spectrograph on the Hobby-Eberly Telescope in Texas, USA, were also used, as well as from the SOPHIE spectrograph at the Observatoire de Haute Provence, in France.

[4] The first exoplanet found around a star similar to the Sun, 51 Pegasi b, was also a hot Jupiter. This was a surprise at the time, as many astronomers had assumed that other planetary systems would probably be like the Solar System and have their more massive planets further from the parent star.

More information:

This research was presented in a paper entitled “Search for giant planets in M67 III: excess of Hot Jupiters in dense open clusters”, by A. Brucalassi et al., to appear in the journal Astronomy & Astrophysics.

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a l: eading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

jeudi 16 juin 2016

When NASA fired up the Additive Manufacturing Facility on the International Space Station to begin more testing of the emerging 3-D printing technology in orbit, one college student in particular watched intently.

In autumn of 2014, a high school senior in Enterprise, Alabama, Robert Hillan entered the Future Engineers Space Tool design competition, which challenged students to create a device astronauts could use in space. The catch was that it must upload electronically and print on the new 3-D printer that was going to be installed on the orbiting laboratory.

In January 2015, NASA and the American Society of Mechanical Engineers Foundation announced that Hillan's design, a Multipurpose Precision Maintenance Tool, was selected out of hundreds of entries to be printed on the station.

Image above: The Mulitpurpose Precision Maintenance Tool, created by University of Alabama in Huntsville student Robert Hillan as part of the Future Engineers Space Tool Challenge, was printed on the International Space Station. It is designed to provide astronauts with a single tool that can help with a variety of tasks, including tightening nuts or bolts of different sizes and stripping wires. Image Credit: NASA.

"Our challenges invite students to invent objects for astronauts, which can be both inspiring and incredibly tough," said Deanne Bell, founder and director of the Future Engineers challenges. "Students must have the creativity to innovate for the unique environment of space, but also the practical, hands-on knowledge to make something functional and useful. It’s a delicate balance, but this combination of creativity, analytical skills, and fluency in current technology is at the heart of engineering education."

Hillan's design features multiple tools on one compact unit, including different sized wrenches, drives to attach sockets, a precision measuring tool for wire gauges, and a single-edged wire stripper. After the new manufacturing facility was installed on the station in March, NASA uploaded Hillan's design to be printed.

As a bonus, Hillan was invited to watch his tool come off the printer from a unique vantage point. On June 15, standing amidst the flight controllers in the Payload Operations Integration Center at NASA's Marshall Space Flight Center in Huntsville, Alabama, which is mission control for space station science, Hillan looked on as NASA astronaut Jeff Williams displayed the finished tool from the station's Additive Manufacturing Facility. The Marshall Center is located just a few miles from where Hillan is a sophomore engineering student at the University of Alabama in Huntsville.

"I am extremely grateful that I was given the opportunity to design something for fabrication on the space station," Hillan said. "I have always had a passion for space exploration, and space travel in general. I designed the tool to adapt to different situations, and as a result I hope to see variants of the tool being used in the future, hopefully when it can be created using stronger materials."

Not only did Hillan get to watch his tool being made, he also got to spend a few minutes chatting with astronauts on the station.

Image above: Robert Hillan, a sophomore engineering student at the University of Alabama in Huntsville, watches a 3-D printer on the International Space Station complete his winning design for the Future Engineers Space Tool Challenge. Part of his prize for winning the competition was going behind the scenes to watch the printing process from NASA's Payload Operations Integration Center -- mission control for space station science located at NASA's Marshall Space Flight Center in Huntsville. Image Credit: NASA.

NASA astronaut Tim Kopra, a current station crew member, congratulated Hillan, saying "When you have a problem, it will drive specific requirements and solutions. 3-D printing allows you to do a quick design to meet those requirements. That's the beauty of this tool and this technology. You can produce something you hadn't anticipated and do it on short notice."

"You have a great future ahead of you."

The space station's 3-D printer caught national headlines late in 2014 when it started operations and built nearly two dozen sample designs that were returned to the Marshall Center for further testing. NASA is continuing 3-D printing development that will prove helpful on the journey to Mars with the newly installed Additive Manufacturing Facility.

Space Station Crew Talks to Student Designer of 3-D Tool

Video above: Aboard the International Space Station, Expedition 47 Commander Tim Kopra and Flight Engineer Jeff Williams of NASA conducted a question and answer session June 15 with a student involved in the design of a concept for 3-D printing aboard the orbital laboratory. Video Credit: NASA.

"When a part breaks or a tool is misplaced, it is difficult and cost-prohibitive to send up a replacement part," said Niki Werkheiser, NASA's 3-D Printer program manager at Marshall. "With this technology, we can build what is needed on demand instead of waiting for resupply. We may even be able to build entire structures using materials we find on Mars."

Space Station Live: 3-D Printing of a Student Design

Video above: NASA Commentator Lori Meggs at the International Space Station Payload Operations Integration Center highlights an education challenge that’s culminated with a student-designed tool being 3-D-printed on orbit. NASA, The American Society of Mechanical Engineers and others sponsored the Future Engineers 3-D Printing in Space Tool Challenge to promote study of design techniques for this new type of manufacturing that will be used by current and future space explorers. Video Credit: NASA.

Winning this competition made Hillan see the space industry in a different light, and it may have changed the direction of his future.

Student Design Printed on ISS 3-D Printer

Video above: The winning entry in the Future Engineers Space Tool Challenge is printed in the Additive Manufacturing Facility on the International Space station. This time-lapse video shows the creation of the Multipurpose Precision Maintenance Tool created by University of Alabama in Huntsville student Robert Hillan. Video Credit: Made In Space.

"When I won the competition, I started seeing problems I face as new opportunities to create and learn," Hillan said. "Since then I have tried to seize every opportunity that presents itself. I love finding solutions to problems, and I want to apply that mentality as I pursue my engineering degree and someday launch my own company."

NASA’s Advanced Exploration Systems Division, in partnership with the American Society of Mechanical Engineers Foundation, continues to provide an ongoing series of Future Engineers 3-D Space Design Challenges. Through these challenges, students become the creators and innovators of tomorrow by using 3-D modeling software to submit their designs of 3-D printable objects for an astronaut to theoretically use in space. See Future Engineers for results and the latest information about the series.

SpaceX is targeting the launch of its Dragon spacecraft from Cape Canaveral Air Force Station in Florida in the early morning hours of July 16, marking the company’s ninth Commercial Resupply Services (CRS-9) flight for NASA. Dragon will deliver nearly 4,900 pounds of cargo, crew supplies, and research experiments to the International Space Station. These experiments include testing capabilities for sequencing DNA in space, regulating temperatures aboard spacecraft, understanding bone loss, and tracking ships around the world. Other investigations study how to protect computers from radiation in space and test an efficient, three-dimensional solar cell.

Biomolecule Sequencer

Image Credits: Oxford Nanopore Technologies

Determining the sequence of an individual organism’s deoxyribonucleic acid or DNA helps us understand how various environments may affect that organism. Currently, DNA sequencing can only be done on Earth, but the Biomolecule Sequencer investigation launching on the Dragon tests a miniature device that could make it possible aboard a spacecraft.

Crew members could use DNA sequencing to identify and monitor microbes and immediately determine appropriate remediation strategies, a capability that will be critical for exploration beyond our moon. Real-time DNA sequencing could help assess crew member health and determine the effectiveness of countermeasures during long spaceflights. It could be integrated into scientific investigations aboard the station and, in the future, analyze DNA-based life that may be found on other worlds. The device also could bring the benefits of DNA sequencing to people in remote and developing locations on Earth.

Phase Change Heat Exchanger

Image Credits: NASA

Space has no atmosphere to protect from temperature extremes of sunlight and shadow. Devices called phase-change material heat exchangers could help maintain critical temperatures inside a spacecraft by freezing or thawing a material. The Dragon launch will carry a new type of heat exchanger to the station for testing. This Phase Change Heat Exchanger Project (Phase Change HX) could lead to better temperature regulation on future missions.

Phase-change material heat exchangers store excess heat or energy by melting a material during peak loads then, when conditions allow, reject the energy through a radiator and freeze the material. The Apollo lunar rover and Skylab used wax as the material, with inconsistent results. Water stores more energy than wax, so a smaller volume of water could be used, but we don’t know how water-based exchangers function in microgravity. Also, water expands when it freezes. This investigation will test both wax and water to determine which would work better as a phase-change heat exchanger on spacecraft.

The investigation also will contribute to more efficient use of phase-change heat exchangers to control temperatures in chemical plants, power plants and other settings on the ground.

OsteoOmics

Image Credit: NASA

Astronauts on long-duration missions and bed-ridden people back on Earth have something in common: bone loss. Scientists study the mechanisms of this bone loss on Earth using a magnetic levitation device to simulate microgravity. The OsteoOmics investigation will test the accuracy of this simulation by comparing genetic changes in bone cells exposed to magnetic levitation on Earth with those exposed to real microgravity aboard the space station.

Improved understanding of the mechanisms behind bone loss could lead to better ways to prevent it during space missions. This also could contribute to better prevention of and treatments for bone loss as a result of diseases like osteopenia and osteoporosis or from prolonged bed rest. Should this investigation determine that ground-based magnetic levitation provides accurate simulation of microgravity, the technique could become an important tool for ground-based investigation of not only bone loss, but other effects of gravitational force on biological systems. OsteoOmics is sponsored by the National Institutes of Health as part of the U.S. National Laboratory, which is managed by the Center for the Advancement of Science in Space (CASIS).

Heart Cells

The Heart Cells investigation studies how microgravity changes the human heart and how those effects vary from one individual to another. This is a U.S. National Lab payload that is sponsored by CASIS.

Future exploration of an asteroid or Mars will require long periods of space travel, which creates increased risk of health problems such as muscle atrophy, including possible atrophy of the heart muscle. For this investigation, scientists induced human skin cells to become stem cells, which can differentiate into any type of cell, and forced them to grow into human heart cells. These heart cells will be cultured aboard the space station for one month and analyzed for cellular and molecular changes. This will provide insight into how microgravity affects the heart. Results could advance the study of heart disease and the development of drugs and cell replacement therapy for future space missions and people with heart disease on Earth.

Maritime Awareness

A world-wide Automatic Identification System (AIS) tracks most ships on the oceans, but the curvature of the Earth blocks signals when ships are far from shore or each other. The U.S. National Lab Maritime Awareness investigation is sending an AIS receiver to the space station for a 12-month test of its ability to continuously monitor ships from above.

Because nothing will block the signal, the system on the station could provide more complete information about world shipping traffic by collecting continuous, real-time information on the identity, position, course, speed, and cargo of ships. These data can improve shipping safety and security, enable monitoring of trade agreements and business interests, and improve enforcement of environmental protections.

NanoRacks – Gumstix

Image Credit: NASA

Radiation bombarding computers in space can interfere with processors and cause malfunctions or loss of data. The lengthy process of testing computers for use in space often puts them two or three generations behind those on Earth. This investigation, NanoRacks-Gumstix, in coordination with CASIS, will place commercially available computers called Gumstix modules on the exterior of the space station to see how the radiation environment affects them. Gumstix modules use processors with tiny gaps between transistors, which make it possible for the computers to be very small. Their small size, however, makes the modules vulnerable to radiation.

A watchdog circuit will keep track of any radiation-related errors during the six-month test. Depending on the results, future miniature spacecraft could use Gumstix to conduct communications and remote sensing research, lowering the cost of access to space.

NanoRacks – Nano Tube Solar Cell

Image Credit: NASA

The NanoRacks-Nanotube Solar Cell investigation launching to the station will study a next-generation, three-dimensional solar cell that absorbs sunlight more efficiently. The US National Lab investigation, sponsored by CASIS, will examine its response to the continually changing sun angles on the space station and the harsh environment of space.

The 3-D, carbon nanotube-based photovoltaic (3DCNTPV) devices are lightweight, flexible, and cost efficient. They also produce more power when the sun isn’t hitting them directly, which eliminates the need for bulky and expensive tracking machinery. In addition, these cells use a copper-zinc-tin-sulfide photoabsorber that has all the traits of an ideal material, including low-cost and abundant chemical elements and compatibility with existing technologies, structures and materials. This technology could improve the efficiency of solar panels on both the space station and on the ground.

These investigations represent just a sampling of science conducted aboard the orbiting lab and the wide range of benefits the research offers both future space exploration and life on Earth.

A newly downlinked spectral observation of Pluto’s moon Nix from NASA’s New Horizons spacecraft provides compelling evidence that its surface is covered in water ice, similar to what the New Horizons team discovered recently for another of Pluto’s small satellites, Hydra. This new result provides further clues about the formation of Pluto’s satellite system.

With this observation by New Horizons’ LEISA – the compositional spectral imager aboard the spacecraft – mission scientists also are piecing together a more detailed picture of Pluto's system of four small, outer moons (Styx, Nix, Kerberos and Hydra).

The deeper spectral features on Nix seen in the graph above are a signature of water ice that is relatively coarse-grained and pure, because the shape and depth of water-ice absorption depends on the size and purity of the icy grains on the surface. Scattering from smaller, or less pure, icy grains tends to wash out spectral absorption features, making them shallower.

Image above: A comparison of the compositional spectra of Pluto’s moons Charon, Nix and Hydra to pure water ice. Nix’s surface displays the deepest water-ice spectral features seen among Pluto’s three satellites – Charon, Nix and Hydra – for which New Horizons obtained surface spectra. Image Credits: NASA/JHUAPL/SwRI.

“Pluto’s small satellites probably all formed out of the cloud of debris created by the impact of a small planet onto a young Pluto,” said New Horizons Project Scientist Hal Weaver, of the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland. “So we would expect them all to be made of similar material. The strong signature of water-ice absorption on the surfaces of all three satellites adds weight to this scenario. Although we didn’t collect spectra of Pluto’s two tiniest satellites, Styx and Kerberos, their high reflectivity argues that they are also likely to have water-ice surfaces.”

The difference in the depths of the water ice absorption features in the Nix and Hydra spectra raises new questions. Specifically, the science team is puzzling over why Nix and Hydra apparently have different ice textures on their surfaces, despite their similar sizes. Another mystery resulting from the Pluto flyby data is why Hydra’s surface reflectivity at visible wavelengths is higher than Nix’s – a New Horizons result published in March in the journal Science – even though Nix’s surface appears to be icier, implying higher reflectivity at visible wavelengths.

The LEISA Nix observation was captured on July 14, 2015, from a range of 37,000 miles (60,000 kilometers), resulting in a spatial resolution of about 2.3 miles per pixel (3.7 kilometers per pixel).

On July 4, NASA will fly a solar-powered spacecraft the size of a basketball court within 2,900 miles (4,667 kilometers) of the cloud tops of our solar system’s largest planet.

As of Thursday, Juno is 18 days and 8.6 million miles (13.8 million kilometers) from Jupiter. On the evening of July 4, Juno will fire its main engine for 35 minutes, placing it into a polar orbit around the gas giant. During the flybys, Juno will probe beneath the obscuring cloud cover of Jupiter and study its auroras to learn more about the planet's origins, structure, atmosphere and magnetosphere.

Image above: This artist's rendering shows NASA's Juno spacecraft making one of its close passes over Jupiter. Image Credits: NASA/JPL-Caltech.

"At this time last year our New Horizons spacecraft was closing in for humanity’s first close views of Pluto,” said Diane Brown, Juno program executive at NASA Headquarters in Washington. “Now, Juno is poised to go closer to Jupiter than any spacecraft ever before to unlock the mysteries of what lies within.”

A series of 37 planned close approaches during the mission will eclipse the previous record for Jupiter set in 1974 by NASA’s Pioneer 11 spacecraft of 27,000 miles (43,000 kilometers). Getting this close to Jupiter does not come without a price -- one that will be paid each time Juno's orbit carries it toward the swirling tumult of orange, white, red and brown clouds that cover the gas giant.

"We are not looking for trouble, we are looking for data," said Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio. "Problem is, at Jupiter, looking for the kind of data Juno is looking for, you have to go in the kind of neighborhoods where you could find trouble pretty quick."

The source of potential trouble can be found inside Jupiter itself. Well below the Jovian cloud tops is a layer of hydrogen under such incredible pressure it acts as an electrical conductor. Scientists believe that the combination of this metallic hydrogen along with Jupiter's fast rotation -- one day on Jupiter is only 10 hours long -- generates a powerful magnetic field that surrounds the planet with electrons, protons and ions traveling at nearly the speed of light. The endgame for any spacecraft that enters this doughnut-shaped field of high-energy particles is an encounter with the harshest radiation environment in the solar system.

"Over the life of the mission, Juno will be exposed to the equivalent of over 100 million dental X-rays," said Rick Nybakken, Juno's project manager from NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. "But, we are ready. We designed an orbit around Jupiter that minimizes exposure to Jupiter’s harsh radiation environment. This orbit allows us to survive long enough to obtain the tantalizing science data that we have traveled so far to get.”

Juno's orbit resembles a flattened oval. Its design is courtesy of the mission's navigators, who came up with a trajectory that approaches Jupiter over its north pole and quickly drops to an altitude below the planet's radiation belts as Juno races toward Jupiter's south pole. Each close flyby of the planet is about one Earth day in duration. Then Juno's orbit will carry the spacecraft below its south pole and away from Jupiter, well beyond the reach of harmful radiation.

While Juno is replete with special radiation-hardened electrical wiring and shielding surrounding its myriad of sensors, the highest profile piece of armor Juno carries is a first-of-its-kind titanium vault, which contains the spacecraft's flight computer and the electronic hearts of many of its science instruments. Weighing in at almost 400 pounds (172 kilograms), the vault will reduce the exposure to radiation by 800 times of that outside of its titanium walls.

Jupiter: Into the Unknown (NASA Juno Mission Trailer)

Video above: Secrets lie deep within Jupiter, shrouded in the solar system's strongest magnetic field and most lethal radiation belts. On July 4, 2016, NASA's Juno spacecraft will plunge into uncharted territory, entering orbit around the gas giant and passing closer than any spacecraft before. Juno will see Jupiter for what it really is, but first it must pass the trial of orbit insertion. Video Credit: NASA Jet Propulsion Laboratory.

Without the vault, Juno’s electronic brain would more than likely fry before the end of the very first flyby of the planet. But, while 400 pounds of titanium can do magical things, it can't do it forever in an extreme radiation environment like that on Jupiter. The quantity and energy of the high-energy particles is just too much. However, Juno’s special orbit allows the radiation dose and the degradation to accumulate slowly, allowing Juno to do a remarkable amount of science for 20 months.

“Over the course of the mission, the highest energy electrons will penetrate the vault, creating a spray of secondary photons and particles,” said Heidi Becker, Juno’s Radiation Monitoring Investigation lead. “The constant bombardment will break the atomic bonds in Juno’s electronics.”

The Juno spacecraft launched Aug. 5, 2011 from Cape Canaveral, Florida. JPL manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. Juno is part of NASA's New Frontiers Program, which is managed at NASA's Marshall Space Flight Center in Huntsville, Alabama, for NASA's Science Mission Directorate. Lockheed Martin Space Systems, Denver, built the spacecraft. The California Institute of Technology in Pasadena manages JPL for NASA.

A small asteroid has been discovered in an orbit around the sun that keeps it as a constant companion of Earth, and it will remain so for centuries to come.

Image above: Asteroid 2016 HO3 has an orbit around the sun that keeps it as a constant companion of Earth. Image Credits: NASA/JPL-Caltech.

As it orbits the sun, this new asteroid, designated 2016 HO3, appears to circle around Earth as well. It is too distant to be considered a true satellite of our planet, but it is the best and most stable example to date of a near-Earth companion, or "quasi-satellite."

"Since 2016 HO3 loops around our planet, but never ventures very far away as we both go around the sun, we refer to it as a quasi-satellite of Earth," said Paul Chodas, manager of NASA's Center for Near-Earth Object (NEO) Studies at the Jet Propulsion Laboratory in Pasadena, California. "One other asteroid -- 2003 YN107 -- followed a similar orbital pattern for a while over 10 years ago, but it has since departed our vicinity. This new asteroid is much more locked onto us. Our calculations indicate 2016 HO3 has been a stable quasi-satellite of Earth for almost a century, and it will continue to follow this pattern as Earth's companion for centuries to come."

Asteroid 2016 HO3 - Earth's Constant Companion

Video Credit: NASA Jet Propulsion Laboratory.

In its yearly trek around the sun, asteroid 2016 HO3 spends about half of the time closer to the sun than Earth and passes ahead of our planet, and about half of the time farther away, causing it to fall behind. Its orbit is also tilted a little, causing it to bob up and then down once each year through Earth's orbital plane. In effect, this small asteroid is caught in a game of leap frog with Earth that will last for hundreds of years.

The asteroid's orbit also undergoes a slow, back-and-forth twist over multiple decades. "The asteroid's loops around Earth drift a little ahead or behind from year to year, but when they drift too far forward or backward, Earth's gravity is just strong enough to reverse the drift and hold onto the asteroid so that it never wanders farther away than about 100 times the distance of the moon," said Chodas. "The same effect also prevents the asteroid from approaching much closer than about 38 times the distance of the moon. In effect, this small asteroid is caught in a little dance with Earth."

Asteroid 2016 HO3 was first spotted on April 27, 2016, by the Pan-STARRS 1 asteroid survey telescope on Haleakala, Hawaii, operated by the University of Hawaii's Institute for Astronomy and funded by NASA's Planetary Defense Coordination Office. The size of this object has not yet been firmly established, but it is likely larger than 120 feet (40 meters) and smaller than 300 feet (100 meters).

The Center for NEO Studies website has a complete list of recent and upcoming close approaches, as well as all other data on the orbits of known NEOs, so scientists and members of the media and public can track information on known objects.

A team of astronomers has used the Atacama Large Millimeter/submillimeter Array (ALMA) to detect glowing oxygen in a distant galaxy seen just 700 million years after the Big Bang. This is the most distant galaxy in which oxygen has ever been unambiguously detected, and it is most likely being ionised by powerful radiation from young giant stars. This galaxy could be an example of one type of source responsible for cosmic reionisation in the early history of the Universe.

Astronomers from Japan, Sweden, the United Kingdom and ESO have used the Atacama Large Millimeter/submillimeter Array (ALMA) to observe one of the most distant galaxies known. SXDF-NB1006-2 lies at a redshift of 7.2, meaning that we see it only 700 million years after the Big Bang.

The team was hoping to find out about the heavy chemical elements [1] present in the galaxy, as they can tell us about the level of star formation, and hence provide clues about the period in the history of the Universe known as cosmic reionisation

Colour composite image of a portion of the Subaru XMM-Newton Deep Survey Field

“Seeking heavy elements in the early Universe is an essential approach to explore the star formation activity in that period,” said Akio Inoue of Osaka Sangyo University, Japan, the lead author of the research paper, which is being published in the journal Science. “Studying heavy elements also gives us a hint to understand how the galaxies were formed and what caused the cosmic reionisation,” he added.

In the time before objects formed in the Universe, it was filled with electrically neutral gas. But when the first objects began to shine, a few hundred million years after the Big Bang, they emitted powerful radiation that started to break up those neutral atoms — to ionise the gas. During this phase — known as cosmic reionisation — the whole Universe changed dramatically. But there is much debate about exactly what kind of objects caused the reionisation. Studying the conditions in very distant galaxies can help to answer this question.

Before observing the distant galaxy, the researchers performed computer simulations to predict how easily they could expect to see evidence of ionised oxygen with ALMA. They also considered observations of similar galaxies that are much closer to Earth, and concluded that the oxygen emission should be detectable, even at vast distances [2].

Colour composite image of distant galaxy SXDF-NB1006-2

They then carried out high-sensitivity observations with ALMA [3] and found light from ionised oxygen in SXDF-NB1006-2, making this the most distant unambiguous detection of oxygen ever obtained [4]. It is firm evidence for the presence of oxygen in the early Universe, only 700 million years after the Big Bang.

Oxygen in SXDF-NB1006-2 was found to be ten times less abundant than it is in the Sun. “The small abundance is expected because the Universe was still young and had a short history of star formation at that time,” commented Naoki Yoshida at the University of Tokyo. “Our simulation actually predicted an abundance ten times smaller than the Sun. But we have another, unexpected, result: a very small amount of dust.”

The team was unable to detect any emission from carbon in the galaxy, suggesting that this young galaxy contains very little un-ionised hydrogen gas, and also found that it contains only a small amount of dust, which is made up of heavy elements. “Something unusual may be happening in this galaxy,” said Inoue. “I suspect that almost all the gas is highly ionised.”

Artist’s impression of the distant galaxy SXDF-NB1006-2

The detection of ionised oxygen indicates that many very brilliant stars, several dozen times more massive than the Sun, have formed in the galaxy and are emitting the intense ultraviolet light needed to ionise the oxygen atoms.

The lack of dust in the galaxy allows the intense ultraviolet light to escape and ionise vast amounts of gas outside the galaxy. “SXDF-NB1006-2 would be a prototype of the light sources responsible for the cosmic reionisation,” said Inoue.

“This is an important step towards understanding what kind of objects caused cosmic reionisation,” explained Yoichi Tamura of the University of Tokyo. “Our next observations with ALMA have already started. Higher resolution observations will allow us to see the distribution and motion of ionised oxygen in the galaxy and provide vital information to help us understand the properties of the galaxy.”

Notes:

[1] In astronomical terminology, chemical elements heavier than lithium are known as heavy elements.

[2] The Japanese infrared astronomy satellite AKARI had found that this oxygen emission is very bright in the Large Magellanic Cloud, which has an environment similar to the early Universe.

[3] The original wavelength of the light from doubly ionised oxygen is 0.088 millimetres. The wavelength of the light from SXDF-NB1006-2 is stretched to 0.725 millimetres by the expansion of the Universe, making the light observable with ALMA.

[4] Earlier work by Finkelstein et al. suggested the presence of oxygen at a slightly earlier time, but there was no direct detection of an emission line, as is the case in the new work.

More information:

This research was presented in the paper entitled: “Detection of an oxygen emission line from a high redshift galaxy in the reionization epoch” by Inoue et al., published in the journal Science.

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Image above: On the left, grid fins are deployed on the Falcon 9 first stage as it returns back towards Earth; on the right, the nozzle of the second stage Merlin Vacuum engine glows bright as the second stage carries the satellites to the targeted orbit.

Eutelsat 117 West B

The two satellites, operated by Eutelsat and ABS respectively, will provide global communication services to a variety of users.

The organic molecule methyl alcohol (methanol) has been found by the Atacama Large Millimeter/Submillimeter Array (ALMA) in the TW Hydrae protoplanetary disc. This is the first such detection of the compound in a young planet-forming disc. Methanol is the only complex organic molecule as yet detected in discs that unambiguously derives from an icy form. Its detection helps astronomers understand the chemical processes that occur during the formation of planetary systems and that ultimately lead to the creation of the ingredients for life.

The protoplanetary disc around the young star TW Hydrae is the closest known example to Earth, at a distance of only about 170 light-years. As such it is an ideal target for astronomers to study discs. This system closely resembles what astronomers think the Solar System looked like during its formation more than four billion years ago.

The Atacama Large Millimeter/Submillimeter Array (ALMA) is the most powerful observatory in existence for mapping the chemical composition and the distribution of cold gas in nearby discs. These unique capabilities have now been exploited by a group of astronomers led by Catherine Walsh (Leiden Observatory, the Netherlands) to investigate the chemistry of the TW Hydrae protoplanetary disc.

Artist’s impression of the disc around the young star TW Hydrae

The ALMA observations have revealed the fingerprint of gaseous methyl alcohol, or methanol (CH3OH), in a protoplanetary disc for the first time. Methanol, a derivative of methane, is one of the largest complex organic molecules detected in discs to date. Identifying its presence in pre-planetary objects represents a milestone for understanding how organic molecules are incorporated into nascent planets.

Furthermore, methanol is itself a building block for more complex species of fundamental prebiotic importance, like amino acid compounds. As a result, methanol plays a vital role in the creation of the rich organic chemistry needed for life.

Catherine Walsh, lead author of the study, explains: “Finding methanol in a protoplanetary disc shows the unique capability of ALMA to probe the complex organic ice reservoir in discs and so, for the first time, allows us to look back in time to the origin of chemical complexity in a planet nursery around a young Sun-like star.”

Gaseous methanol in a protoplanetary disc has a unique importance in astrochemistry. While other species detected in space are formed by gas-phase chemistry alone, or by a combination of both gas and solid-phase generation, methanol is a complex organic compound which is formed solely in the ice phase via surface reactions on dust grains.

Artist’s impression of the disc around the young star TW Hydrae

The sharp vision of ALMA has also allowed astronomers to map the gaseous methanol across the TW Hydrae disc. They discovered a ring-like pattern in addition to significant emission from close to the central star [1].

The observation of methanol in the gas phase, combined with information about its distribution, implies that methanol formed on the disc’s icy grains, and was subsequently released in gaseous form. This first observation helps to clarify the puzzle of the methanol ice–gas transition [2], and more generally the chemical processes in astrophysical environments [3].

Ryan A. Loomis, a co-author of the study, adds: “Methanol in gaseous form in the disc is an unambiguous indicator of rich organic chemical processes at an early stage of star and planet formation. This result has an impact on our understanding of how organic matter accumulates in very young planetary systems.”

Methanol around the young star TW Hydrae

This successful first detection of cold gas-phase methanol in a protoplanetary disc means that the production of ice chemistry can now be explored in discs, paving the way to future studies of complex organic chemistry in planetary birthplaces. In the hunt for life-sustaining exoplanets, astronomers now have access to a powerful new tool.

Notes:

[1] A ring of methanol between 30 and 100 astronomical units (au) reproduces the pattern of the observed methanol data from ALMA. The identified structure supports the hypothesis that the bulk of the disc ice reservoir is hosted primarily on the larger (up to millimetre-sized) dust grains, residing in the inner 50 au, which have become decoupled from the gas, and drifted radially inwards towards the star.

[2] In this study, rather than thermal desorption (with methanol released at temperatures higher than its sublimation temperature), other mechanisms are supported and discussed by the team, including photodesorption by ultraviolet photons and reactive desorption. More detailed ALMA observations would help to definitely favour one scenario among the others.

[3] Radial variation of chemical species in the disc midplane composition, and specifically the locations of snowlines, are crucial for understanding the chemistry of nascent planets.The snowlines mark the boundary beyond which a particular volatile chemical species is frozen out onto dust grains. The detection of methanol also in the colder outer regions of the disc shows that it is able to escape off the grains at temperatures much lower than its sublimation temperature, necessary to trigger thermal desorption.

More information:

This research was presented in a paper entitled “First detection of gas-phase methanol in a protoplanetary disk”, by Catherine Walsh et al., published in Astrophysical Journal, Volume 823, Number 1.

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.